1. Field
One embodiment of the present invention relates to a cooling device for cooling a plurality of heating elements. Another embodiment of the present invention relates to an electronic apparatus equipped with the cooling device.
2. Description of the Related Art
An electronic apparatus, including a portable computer, has a plurality of heating elements such as a CPU and a VGA (Video Graphics Array).
The amount of heat originating from the CPU and the VGA increases in accordance with an increase in the processing speed of the CPU and the VGA or as the CPU and the VGA become multifunctional. As the amount of heat increases, the CPU and VGA operate less efficiently or become inoperative.
As a cooling device that cools a plurality of heating elements, there has been proposed a structure that is used commonly for the heating elements and has a passage thermally connected to respective heating elements. Coolant circulates through the passage. Since the passage is used commonly among the plurality of heating elements, the number of parts of the cooling device is reduced, thereby simplifying the structure of the cooling device (see, e.g., JP-A-2001-68887).
Meanwhile, an electronic apparatus is tend to be slimmed down. In accordance with slimming down, a cooling device for cooling a heating element, such as a CPU, is also tend to be made slim. As a measure for slimming the cooling device, a passage through which a coolant flows has been formed thin.
In order to prevent reduction in the strength of the passage, which would otherwise be caused by slimming down, a multi-hole pipe having a plurality of holes is adopted for the passage. Since partition walls that partition the holes function as columns, the required strength of the multi-hole pipe is ensured.
The multi-hole pipe of this type is formed by means of, e.g., extrusion molding (see, e.g., JP-A-2000-193385).
Alternatively, the multi-hole pipe of this type has a structure having a first plate-like body whose one surface has a plurality of protruding sections, and a second plate-like body having recessed sections to fit the protruding sections. By means of the protruding sections of the first plate-like body fitting the recessed sections of the second plate-like body, the protruding sections and the recessed sections constitute partition walls, to thus form a plurality of holes (see, e.g., JP-A-2005-7459). The first and second plate-like bodies disclosed in JP-A-2005-7459 are formed by means of rolling.